Year: 2022
Type: conference-paper
Abstract: Many river mouths presenting a seasonal variation of flow suffer of periodically (semi-) closure of their channels by the development of sand spits.Due to their low elevations, they are subject to different levels of coastal flooding during storm events.This is the case of the microtidal mouth of the Têt (Canet en Roussillon, Occitanie) which has a persistent sandy spit in its northern part.In order to study the impact of marine energy events on the morphology of this spit, high-frequency hydrodynamic measurements, video and topographic surveys by UAV were set up on a monthly basis and before and after each potentially morphogenic event.The analysis of twelve marine storms showed a linear relationship between the significant wave height and the mode of overtopping over the spit, ranging from a few localised overtopping to complete coastal flooding for several hours.Four morphogenic response thresholds were identified, allowing us to predict the behaviour of this sandy spit as a function of coastal flooding hazards.On the other hand, it seems that the pre-existing morphology of the spit, in particular the altitude of its crest, modulates the extent of the overtopping, although there does not seem to be any systematic control.
Language: French
Topic: Coastal and Marine Dynamics
Subfield: Earth-Surface Processes
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W4317999727